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US3673288A
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Microwave method for tempering tar-bonded refractory bricks
Assignee: FNB Financial Co
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Filing: 1970-09-17
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Granted: 1972-06-27
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Expires: 1990-09-17
Abstract
Abstract Tar-bonded basic refractory articles such as tar-bonded bricks and the like, are heated to tempering temperatures by the application of microwave energy. Tempering may be completely or partially carried out by the microwave heating operation.
Inventors
- 👤 Edwin E Childs Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:57
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/03
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
26 words
The method of claim 1 wherein the shaped articles are heated to a temperature of about 550* to 600* F. by the application of microwave energy.
Claim 2
Dependent Claim
26 words
The method of claim 2 wherein the shaped articles are subjected to microwave heating at a maximum temperature of about 600* F. for approximately 1/2 hour.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein the shaped articles are subjected to further tempering by the application of external heat following the initial microwave heating.
Claim 4
Dependent Claim
17 words
The method of claim 4 wherein the tempering is conducted at a temperature of about 600* F.
Claim 5
Dependent Claim
28 words
The method of claim 5 wherein the shaped articles are further heat tempered by the application of external heat for a period of about 2 to 3 hours.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein the microwave energy applied to said articles has a frequency of 2,450 megacycles per second.
Claim 7
Dependent Claim
44 words
The method of claim 1 wherein the amount of tar in said mixture is no more than about 4.5 percent, based on the weight of the mineral aggregate, and the microwave energy applied to said articles has a frequency of 915 megacycle per second.
Claim 8
Dependent Claim
162 words
In a method of manufacturing refractory shaped articles having a thermally decomposible hydrocarbon bond wherein refractory particles consisting essentially of dead-burned dolomite, periclase, magnesite or mixtures thereof are mixed at ambient temperature with from about 3 to 7 percent by weight of a hydrocarbonaceous binder that is liquid at ambient temperature consisting essentially of tar, low melting point petroleum hydrocarbon resins, solvent fuel oil containing paraffin wax, or mixtures thereof, the mixture is pressed into desired shapes and the shaped articles are subjected to a tempering treatment below coking temperature of the binder prior to use, the improvement comprising raising the temperature of the shaped articles uniformly and rapidly throughout their entire mass to tempering temperature in the range of 400* to 700* F. by subjecting said articles to microwave energy in the range of about 900 to 25,000 megacycles per second, the amount of binder being no more than about 4.5 percent when microwave energy of about 900 megacycles is used.
Claim 9
Dependent Claim
22 words
The method of claim 9 wherein the aggregate is mixed with a low melting point petroleum hydrocarbon resin and finely divided carbon.
Claim 10
Dependent Claim
21 words
The method of claim 9 wherein the aggregate is mixed with powdered pitch and a solvent fuel oil containing paraffin wax.
Claim 11
Dependent Claim
23 words
The method of claim 9 wherein the aggregate is mixed with a solvent fuel oil containing paraffin wax and with finely divided carbon.
References Cited (Backward Citations)
US3168602A
Cited
US3261959A
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US3449213A
Cited
US3368010A
Cited
US3519517A
Cited
US3468683A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |